1. Technical Field
The present disclosure generally relates to a radiation pattern insulator and more particularly to a radiation pattern insulator in a multiple antennae system, the antenna system, and the communication device using the same.
2. Background
The current wireless communication system usually adopts the multiple input multiple output (MIMO) wireless transmission technology, such as the wireless communication system of standard 802.11n or the worldwide interoperability for microwave access (WiMAX) system adopting standard 802.16, so as to increase the data transmission rate by increasing the wireless channel number. However, to achieve the object of the MIMO technology, the communication device of the user must have multiple antennae. If the distance of the multiple antennae on the communication device is not far enough, the wireless signals will be mutually coupled when the multiple antennae receive or transmit the electromagnetic waves of the wireless signals, so that the insulation of the multiple antennae will be decreased, and thus the total capacity of the wireless channels will be decreases. Hence, it is important to efficiently increase insulation of the multiple antennae for the MIMO technology and the communication device with multiple antennae.
Several conventional methods for increasing insulation of the multiple antennae are proposed and described as follows. One method is to increase the distance of the multiple antennae. However this method needs much space to be occupied, and is not suitable for the hand-held or small volume communication device, such as the mobile phone, the notebook, or the personal data processing apparatus. Another method is to use multiple antennae with different polarizations and radiation patterns. However, when the hand-held or small volume communication device adopts this method, it is hard to obtain the pure polarization or the definite radiation. Another method is to use the hybrid coupler to achieve the diversity of the wireless signals, and another method is to use the single insulation architecture, such as passive antennae. Another method is to use the period insulation architecture, but this method may deduce a narrow frequency band.